One zipper is functional. Two zippers, both of which open from either direction, do not appear to have much of a purpose. I guess because it’s like you’re getting four zippers for the price of two?
You know what goes with two multi-directional zippers? Slippery lining-style fabric, as is featured on this dress.
Basically, you’re looking at stiff, ugly fabric that is apparently slippery, with multiple zippers. Sounds appealing and totally useful.